Composite material for a permeable reactive barrier

ABSTRACT

Compositions in accordance with the principles of the present invention comprise a compressed mixture of fibrous organic materials and multi-valent metals used to remove organic chemical contaminants. The compositions are made into a pre-shaped, compressed form used to form a permeable reactive barrier for decontamination of soils, sediments, sludges, and waters containing environmental pollutants. The compressed mixture, comprising the fibrous organic particles and one or more multivalent metallic particles, is formed into reactive pellets, granules, and other pre-shaped structures for use in constructing a reactive barrier, typically for use in a contaminated environment or in an industrial process. By way of example, the pre-shaped structure may be used to construct a reactive barrier to remove halogenated organic chemical contaminants, nitroaromatic organic contaminants, or certain inorganic contaminants from various terrestrial and aquatic based ecosystems.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from and is related to U.S. ProvisionalPatent Application No. 60/451,467 titled “Pelletized Material for aPermeable Reactive Barrier” filed Mar. 3, 2003.

FIELD OF THE INVENTION

The invention relates to the removal of contaminants.

BACKGROUND OF THE INVENTION

Many halogenated and nitroaromatic organic chemical contaminants in theenvironment are highly resistant to degradation. Once the halogenatedorganic chemical contaminant is dehalogenated or the nitro groups arereduced to amine groups, the organic contaminants are usually degradedeasily, generally by aerobic microbial processes. Degradation of organiccontaminants in microbial ecosystems occurs both by enzymatic andnon-enzymatic mechanisms. Most enzymatic reactions involve wholemicrobial cells such as bacteria, fungi, and algae. Enzymatic reactionsare usually more specific than non-enzymatic reactions, but the activityof enzymatic reactions is destroyed by harsh conditions such as exposureto high temperatures. Microbial activity can assist degradation oforganic contaminants either directly by enzyme production or indirectlyby maintaining the reducing conditions of the environment. Either way,microbial activity enhances both the inorganic and biochemicalmechanisms by which degradation of organic contaminants occurs.

Currently, certain environmental remediation methods employ the use ofrelatively small, finely comminuted, segregated particles of varioustypes of materials that are typically mixed on site, in proportions andamounts selected by on-site personnel. For example, where such materialsare used, on-site personnel are required to thoroughly mix quantities ofthe various components and, in most instances, incubate small batches ofmixtures to establish sufficient beneficial microbial growth to permituse. The personnel must then apply those incubated components into thetarget environment. In these prior art systems, on-site personnel haveused iron filings alone, comminuted fibrous organic materials alone,iron filings combined and then mixed on site with comminuted fibrousorganic materials or iron filings mixed on site with sand.

Many earlier systems using iron filings alone, comminuted organicmaterials alone, or even iron filings with sand, are often ineffectivein treating sites which are contaminated with various organic chemicals.Each of these systems sought to use individual ingredients provided inthe form of relatively fine, segregated particles of one or moreingredients, to obtain a relatively high reactive surface area pervolume (and hence weight and expense) of the material to be added to thecontaminated site.

Even those systems contemplating the use of more than one additiveencounter problems relating to on-site measurement, mixing, andapplication of the ingredients to the target area. By way of example,there is a tendency for on-site personnel to inadequately mix thedesired components, often leading to pockets or zones with too much ortoo little of a desired ingredient. Even if the ingredients wereadequately mixed, the ingredients might not be mixed in appropriateratios to achieve target concentrations determined to be optimal for theparticular application. Mixtures of two or more ingredients also had atendency to stratify due to differences in physical properties such asdensity and average particle sizes. In addition, even where prior artsystems contemplated the mixture of fine particles of two or moreingredients, various transportation and handling problems would arise.Some ingredients tended to generate dust and other unpleasant handlingconditions for on-site personnel.

Therefore, there is a need for a composition for treating contaminatedregions that is easy to use, economical, and effective.

SUMMARY OF THE INVENTION

Compositions in accordance with the principles of the present inventionare easy to use, economical, and effective. A composition in accordancewith the principles of the present invention comprises a compressedmixture of fibrous organic materials and multi-valent metals used toremove organic chemical contaminants. The compressed mixture—comprisingthe fibrous organic particles and one or more multivalent metallicparticles—is formed into reactive pellets, granules, and otherpre-shaped structures for use in constructing a reactive barrier,typically for use in a contaminated environment or in an industrialprocess. In one embodiment of the present invention, for example, thepre-shaped structure may be used to construct a reactive barrier toremove halogenated organic chemical contaminants, nitroaromatic organiccontaminants, and certain inorganic chemical contaminants from variousterrestrial and aquatic based ecosystems. In one application, apermeable reaction barrier is used in accordance with the principles ofthe present invention.

Compositions in accordance with the principles of the present inventionmay comprise a pre-shaped structure. In one embodiment of the presentinvention, the pre-shaped structure comprises a compressed mixture oforganic matter, preferably comminuted and fibrous, and a metal,preferably comminuted elemental iron in its zero valent form.Preferably, the pre-shaped structure is rigid. The ingredients of thecomposition of the present invention may be supplemented with binders,water, pH buffering agents, or other materials designed to conferspecific characteristics upon the pre-shaped structure. One embodimentof the present invention is illustrated in FIG. 2. As seen in FIG. 2,composite material in accordance with the principles of the presentinvention comprises a slow release solid carbon 21, a zero valent ironparticle 23, and a pH buffering agent 25 such as zeolite. A pre-shapedstructure in accordance with the present invention may be used as anadditive to contaminated environments in both terrestrial and aquaticsystems, or as an additive to industrial and effluent treatmentequipment and systems.

The present invention provides a number of advantages over the prior artenvironmental remediation methods. Compositions in accordance with theprinciples of the present invention may be employed for the treatment ofsolid materials such as but not limited to soil, sediment, or sludge, orfor treatment of liquid materials such as but not limited togroundwater, surface waters, or industrial process waters. In general,compositions in accordance with the principles of the present inventionhave utility wherever contaminants may be destroyed by exposing them tostrong reducing conditions. Specific examples include but are notlimited to dechlorination and debromination of chlorinated or brominatedorganic compounds, reduction of nitro-substituted organic compounds, andreduction of nitrate and perchlorate in either terrestrial or aquaticenvironments. Reduction of certain metallic contaminants is alsopossible in cases when their reduction converts the metal into a lesssoluble form that will precipitate in the reactive barrier. Compositionsin accordance with the principles of the present invention areparticularly well suited to use in, for example but not limited to,treatment of contaminated groundwater as it passes through a reactivebarrier such as a wall-type structure, an enriched region of the nativeaquifer material, a bed, or a column through which the contaminatedwater is made to flow.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional diagram of a permeable reaction barrier inaccordance with the principles of the present invention for thetreatment of groundwater;

FIG. 2 is a cross-sectional view of composite material in accordancewith the principles of the present invention for use in a permeablereaction barrier for groundwater treatment.

FIG. 3 is a chart comparing the pH produced in traditional ZIV permeablereaction barriers with the pH produced a permeable reaction barrier inaccordance with the principles of the present invention;

FIG. 4 is a chart comparing the Eh produced in a traditional ZIVpermeable reaction barriers with the Eh produced a permeable reactionbarrier in accordance with the principles of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention relates to compositions for treating contaminatedregions that are easy to use, economical, and effective. Compositions inaccordance with the principles of the present invention provide anadmixture of organic and inorganic particles that have been formed intoa pre-shaped structure. In one embodiment of the present invention, thepre-shaped structure is preferably a cylindrical pellet or a rectangularprism such as a cube. It is desirable to combine the organic andinorganic materials into a pre-shaped structure to ensure that the twoclasses of ingredients are uniformly and intimately co-mingled so thatthe key individual components (i.e., the organic particles that serve asfood for microorganisms and the inorganic particles that serve aschemical oxygen scavengers) are and will continue to be uniformlydistributed throughout a reactive barrier (PRB), or soil, for arelatively long period of time. As seen in FIG. 1, the PRB 11 issituated near the contaminated region, for example contaminatedgroundwater 13. Preferably the PRB 11 is situated in close proximity butsomewhat downstream from the contaminated groundwater 13. Thecontaminated water flows a direction 17, enters the PRB 11 where thedecontamination occurs and treated groundwater 15 exits the PRB 11.

The pre-shaped structure of the present invention is a combination oforganic matter and certain multi-valent metal particles. The organicmatter is capable of supporting organisms such as but not limited tomicroorganism (e.g. bacteria) or fungal growth. The pre-shaped structureis added to soil, water, sediment, and environments containing organiccontaminants such as nitroaromatic organic chemicals and halogenatedorganic chemicals. This is done in order to provide an environment thathas a stable negative redox potential, that is, a reducing environmentthat is conducive to reduction of nitro groups to amine groups and thereductive dehalogenation and subsequent enhanced degradation ordecomposition of the nitroaromatic and halogenated organic contaminants.

Microorganisms should be present in the reactive barrier, soil, or waterduring operation or use. Generally, the necessary microorganisms areindigenous to the organic material ingredients in the pre-shapedstructure and in the contaminated environment. Where it is desirable ornecessary to do so, additional microorganisms may be added as asupplement to the contaminated environmental sector or system. In someembodiments of the present invention, it may be desirable to addmicroorganisms as one of the ingredients included in the pre-shapedstructure; however, it is not essential that the microorganisms be addedto the compressed material. For example, in one embodiment of thepresent invention the microorganisms are applied separately to thereactive barrier during or after construction. Other approaches forensuring adequate microbial growth also are possible and will beunderstood by those skilled in the art.

For purposes of explanation only and not by way of limitation, it isbelieved that the organic matter provides nutrients for aerobic andfacultatively anaerobic microorganisms. The growth of thesemicroorganisms consumes oxygen, which promotes anaerobic conditions andin turn lowers the redox potential of the environment. The redoxpotential also may be lowered by reducing compounds such assulfur-containing amino acids and the like, which may be present in theorganic matter, and also may be lowered by the reducing power of themulti-valent metal particles.

This environment promotes the growth of anaerobic microorganisms whoseactivity lowers and maintains a strong negative redox potential, thatis, it creates strong reducing conditions that are conducive toreductive degradation of nitroaromatics and to dehalogenation reactions.The resulting system contains a wide spectrum of inorganic, biochemical,and enzymatic redox systems, some or all of which promote the reductivedegradation of nitroaromatic organic contaminants and dehalogenation ofthe halogenated organic contaminants. After degradation of the nitrogroups and/or dehalogenation of the halogenated organic contaminants,the organic contaminants tend to be more readily degradable; thus, theorganic contaminants will rapidly decompose or decay by naturalprocesses in the environment, particularly if aerobic conditions aresubsequently allowed or maintained.

The organic matter of the present invention should be suitablycomminuted to a size and typical particle shape that will allow it to bereadily mixed with the other ingredients, such as but not limited tocomminuted multi-valent metallic particles. The organic ingredients alsoshould be capable of supporting bacterial or fungal growth in thereactive barrier. It is believed that the use of fibrous organic matterpermits temporary absorption of the nitroaromatic and halogenatedorganic chemical contaminants into the fibrous structure, therebyenhancing the extent of contaminant degradation and removal from theenvironment. Suitable fibrous organic matter is generally derived fromplant matter such as but not limited to crops, crop residues, bushes ortrees including their byproducts (for example sawdust), grass and weeds,and algae.

In certain embodiments of the present invention, it also may bebeneficial to blend different sources of plant matter together. Plantmatter that is high in nitrogen content, for example but not limited to,leguminous plant matter is particularly preferred. Alternatively, theplant matter may be supplemented with nitrogenous material such as butnot limited to amines and nitrates, including but not limited toammonium nitrate, urea, calcium nitrate, the like, and mixtures thereof.The plant matter also may be supplemented with other fibrous ornon-fibrous organic matter such as simple carbon sources including butnot limited to carbohydrates such as sugars, organic acids such aslactic acids, the like and mixtures thereof. Complex organic matter alsomay be used, including but not limited to sewage sludge, potatoprocessing waste, molasses, spent distiller grains, spent coffeegrounds, the like and mixtures thereof.

The fibrous organic matter is preferably cut or comminuted into smallparticles in order to increase the exposed surface area of the organicingredients to be mixed, compressed, and shaped with the multi-valentmetallic ingredients. While the particle size of the fibrous organicingredients is not critical to the present invention, generally it ispreferred that the fibrous organic ingredients will be comminuted to aneffective diameter or size that will often be considerably smaller thanthe overall size of the compressed structure. For example, the fibrousorganic particles are preferably in the range of from about 0.001 mm toabout 5 mm. In certain embodiments of the present invention it also willbe preferred that the comminuted fibrous organic material will be highlyresistant to premature or excessive microbial degradation. Comminutedfibrous organic material that are highly resistant to premature orexcessive microbial degradation include for example, but not limited to,finely comminuted particles made from coconut, walnut, or almond shells.However, other fibrous organic plant materials also may be used, bearingin mind the conditions under which the pre-shaped structure will beused.

Suitable multi-valent metal particles for use in the present inventioninclude those multi-valent metals that are capable of being oxidized andreduced under normal environmental conditions, and which have averageparticle diameters ranging from about 0.001 mm to about 5 mm. Amongthese would be the elemental or zero valent forms of many common metalssuch as but not limited to iron, magnesium, zinc, and aluminum. Iron,magnesium, and mixtures thereof are the most preferred metals due totheir moderately low toxicity and good reducing power. Other preferredmulti-valent metals for use in this invention include zinc, copper,cobalt, nickel, and mixtures thereof. However, due to the relativelyhigh toxicity of these metals, they are generally added in lowerconcentrations to minimize their own detrimental effects on treatedsoil, sediment, sludge, water, and other environmental systems.

In the pre-shaped structure of the present invention, the resultingweight ratio of metal particles to comminuted fibrous organic matterranges from about 1:1 to about 1:500,000 respectively. When themultivalent metal particles comprise iron, magnesium, or mixturesthereof, the weight range of metal particles to organic matter ispreferably in the range about 1:1 to about 1:10,000 respectively. Whenthe multivalent metal particles comprise zinc, copper, cobalt, nickel ormixtures thereof, the weight range of metal particles to comminutedorganic matter is preferably in the range about 1:10 to about 1:500,000respectively.

Mixtures of metal particles also may be included in the pre-shapedstructure of the present invention. For example, some redox systems suchas those based on porphyrins are complexed with iron while others suchas corins are complexed with cobalt. Thus, it may be advantageous totreat some contaminated environments with a pre-shaped structureincluding a combination of multi-valent metals such as but not limitedto a mixture of iron and cobalt. One of ordinary skill in the art wouldunderstand from the teachings of the present invention that numerousredox systems could be used, thereby utilizing various compounds andmetals without departing from the scope and intention of the presentinvention.

The pre-shaped structure also may be made from a mixture of ingredientsincluding porosity enhancers. For example, zeolite, bentonite, sand,glass particles, fibers and filaments, and other inert particulates maybe added to enhance the effective surface area of the pre-shapedstructure, including pellets and cubes.

Other additives included in admixture with the pre-shaped structure mayinclude fats and oils made available because of desirable chemical andphysical properties. For example, some fats and oils may be useful ascoating agents, to protect the organic particles against premature orexcessive degradation. Other fats and oils may be selected because theyalso may retard excessive growth of certain microbial colonies.Furthermore, some fats and oils may be useful additives because of theirsuitability to act as binding agents, and in some instances because ofother, additional, desirable performance qualities.

Other suitable binding agents may be selected from commerciallyavailable sources. The binding agents will most often be selected afterconsideration of their long term effectiveness in maintaining therigidity and permanence of the compressed material structure, theirimpact on microbial growth, and the absence of any significant negativeimpact on the surrounding environment. Preferably, the binding agentwill be inert and will not detrimentally affect performance of thereactive barrier, microbial growth and related chemical processes, orthe quality of the treated soil, sludge, sediment, water or othersystem.

In one embodiment of the present invention, a pre-shaped, compressedpellet or cube is made from a mixture of finely comminuted fibrousorganic material and fine iron filings in which the weight ratio of ironto organics is about 1:20. In a preferred embodiment of the presentinvention, the mixture used to manufacture the pre-shaped structureincludes an amount of fine iron filings representing a concentration ofabout 5% to about 20% (weight by weight) of the compressed mixture, anamount of comminuted fibrous organic material (such as comminuted plantmaterial) representing about 5% to about 80% (weight by weight) of thecompressed mixture, an amount of porosity enhancer representing up toabout 90% (weight by weight) of the compressed mixture, and a minoramount of binding agent (representing less than about 1% to about 2%(weight by weight) of the compressed mixture).

In another embodiment of the present invention, a pre-shaped, compressedstructure comprises a mixture of solid inorganic and solid organicparticles formed into a rigid structure for use in environmentalremediation. In a preferred embodiment of the present invention, theinorganic portion comprises iron particles and the organic portioncomprises comminuted fibrous organic material, such as comminuted plantmatter. These solid particulate ingredients may be supplemented andmixed with liquids including water and fats or oils to aid in processingor to confer specific nutritional, physical, or chemical characteristicsto the finished structure. For example, fats or oils may be added toslow the rate at which the organic material is biodegraded bymicroorganisms after the structure has been placed into the contaminatedsoil or water. By way of further example, a preferred fatty additive mayinclude lanolin because of its hydrophobic qualities, particularly whenused to coat fibrous organic ingredients, and to slow microbialdegradation of the fibrous organic material in the pre-shaped structure.In some embodiments, other fats and oils may be used as an additive toenhance microbial growth. By way of further example, water or fluids andbinding agents may be used during processing to aid in mixing andcompaction of the organic and inorganic ingredients.

In some embodiments of the present invention it will be preferred thatother additives will be non-biodegradable and inert. Some additives maybe desirable as performance enhancers and other additives may beselected as retardants to slow or inhibit certain undesirable reactionsand processes. Zeolite also is an example of a performance enhancer whenadded as an ingredient for increased porosity, pH buffering, ionexchange capability, or other benefits. Additives having nutritivequalities also may be included in admixture with the pre-shapedstructure of the present invention.

Although the preferred shapes of the pre-shaped structure of the presentinvention will most often be in the form of cylindrical pellets orcubes, many other shapes and configurations will be possible. Forexample, irregular shapes may be desirable so that, when the pre-shapedstructures are placed into the target bed, column or other system,certain fluid flow patterns will be experienced or other performancecharacteristics will be achieved for the particular field of use. By wayof further example, it may be desirable to form hollow cylinders, rings,or saddle shaped structures so that the hollow cylinders, rings, or“saddles”, when placed into a column or other reactive barrier, willcreate many intricate and interconnecting fluid flow channels along thelength of the reactive barrier. It also may be desirable to utilize morethan one form of pre-shaped structure in any given application. In otherembodiments of the present invention, it may be desirable to providecompact, relatively uniform structures that will stack tightly whenplaced into a column or other barrier to provide fewer and morerestricted fluid flow channels to reduce the rate of flow through thereactive barrier and to increase the time available for the contaminantsto react before they are carried out of the reactive barrier by, forexample, flowing water.

In a preferred embodiment of the present invention, the pre-shaped rigidstructure is compressed to a density greater than that of water or ofmost aqueous systems, to inhibit flotation, migration, or escape of thepre-shaped structure, such as pellets and cubes, from the intendedtarget site. Additives may be included in the mixture to maintain theshape and rigidity of the preshaped structure over the contemplateduseful life of the reactive barrier.

It is expected that certain embodiments of the pre-shaped structureincluded in the present invention will be manufactured in standard feedmills or standard flour mills. Such pre-shaped structures will often beconfigured as, cylindrical pellets with diameters of between about 1/16inch and about ¼ inch and lengths of up to about 1 inch. In addition,many mills are be capable of manufacturing cubes that can havedimensions from as small as about 25 mm square to about 30 mm×70 mm.

It may be possible to achieve a more complete or effective treatment orremoval of contaminants with the present invention because theingredient materials are combined to create an environment conducive toremoval of contaminants (that is, the inorganic particles and theorganic particles). The ingredients are intimately mixed, thencompressed together into a homogenous, pre-shaped structure. Thispre-shaped structure will tend to minimize or eliminate the problem ofstratification of materials in the soil, sediment, sludge, bed, column,reactive wall, or other permeable reactive barrier that might otherwiseoccur due to differences in densities and particle sizes of theindividual components.

Lower materials costs may be achieved with the present invention becausethe pre-shaped product will have a higher overall density, resultingfrom compressing and shaping the organic and inorganic particles (andwhere appropriate, other ingredients). The ingredients are shaped andcompressed into a larger, denser structure, which will tend to, amongother benefits, reduce transportation costs.

It may be possible to build the reactive barrier, such as a reactivewall or column, more quickly with the present invention; therebyincurring lower construction costs. Currently, the rate of filling areactive barrier is slow because the various conventional, particulatematerials to be placed in the barrier must be thoroughly mixed prior toplacement and only small amounts of the conventional materials areplaced at one time in an effort to reduce stratification of thematerials due to large differences in density.

In many instances, reactive barriers of the present invention will tendto have a longer effective life. The organic material contained withinthe pre-shaped structure, which has been compressed into a shape such asbut not limited to a dense pellet or cube, has less available surfacearea per unit of volume and, hence, will be more slowly biodegraded bymicroorganisms. The compressed nature of the organic and inorganicparticles results in a slower-release of nutrients and carbon tomicroorganisms present in the water, sediment, or soil. In certainembodiments of the present invention it also may be desirable andadvantageous to incorporate into the pre-shaped structure an ingredientdesigned to inhibit biodegradation of the organic portion of the pellet,cube, or other pre-shaped structure, to thereby further lengthen theeffective life of the treatment system.

It may be possible to achieve a longer effective life of the inorganicportion of the pre-shaped structure of the present invention due to aseries of favorable biochemical reactions that take place asmicroorganisms consume the organic portion of the structure in veryclose proximity to the inorganic portion. Specifically, it is believedthat when the inorganic portion is composed of elemental iron in itszero-valent form, the surface of the iron will be continuously exposedto organic acids which are released as microorganisms anaerobicallymetabolize the organic portion of the structure. Exposure to the organicacids, including acetic, propionic, and butyric acid, will reduce therate at which the surface of the iron particles is occluded byprecipitates, such as carbonates, iron oxides, or iron hydroxides, whichare often abundant in soil and water. This phenomenon is illustrated bythe fact that pH remains substantially lower in a PRB 11 composed of thecomposite material of the present invention than in a PRB 11 composed ofzero-valent iron alone. FIG. 3 illustrates that the pH produced in atraditional zero-valent iron permeable reaction barriers is not asacidic as the pH produced a permeable reaction barrier in accordancewith the principles of the present invention. This favorable alterationof the pH in the PRB 11 does not alter its ability to destroycontaminants since the redox conditions in the PRB 11 composed of thecomposite material is as negative, or more negative, as those found in aPRB 11 composed solely of zero-valent iron. As seen in FIG. 4 the Ehproduced in a traditional zero-valent iron permeable reaction barriersis not low as the Eh produced a permeable reaction barrier in accordancewith the principles of the present invention.

The foregoing are examples of certain embodiments of the presentinvention. Many other embodiments, including modifications andvariations thereof, also are possible and will become apparent to thoseskilled in the art upon a review of the invention as described herein.Accordingly, all suitable modifications, variations and equivalents maybe resorted to, and such modifications, variations and equivalents areintended to fall within the scope of the invention as described hereinand within the scope of the issued patent claims.

1. A method of removing contaminates from an area of contaminationcomprising: providing a pre-shaped, compressed mixture including aneffective amount of fibrous organic material capable of supportingbacterial growth and an effective amount of multivalent inorganicmaterial capable of removing organic chemical contaminants; placing thepre-shaped, compressed mixture in the area of contamination to form apermeable reactive barrier for decontamination; and providing anenvironment to promote conversion of the contaminants to less harmfulcompounds.
 2. The method of claim 1, wherein the multivalent inorganicmaterial is a metal.
 3. The method of claim 2, wherein the metal istaken from the group consisting of zinc, copper, cobalt, nickel, andmixtures thereof.
 4. The method of claim 2, wherein the metal is takenfrom the group consisting of iron, magnesium, and mixtures thereof. 5.The method of claim 1, wherein the fibrous organic material is plantmatter.
 6. The method of claim 5, wherein the plant matter is leguminousplant matter.
 7. The method of claim 1 further comprising nitrogenousmaterial.
 8. The method of claim 1 further comprising simple carbonsources.
 9. The method of claim 1 further comprising complex carbonsources.
 10. The method of claim 1 further comprising shaping thepre-shaped compressed mixture into a pellet.
 11. The method of claim 1further comprising shaping the pre-shaped, compressed mixture into acube.
 12. The method of claim 1 further comprising shaping thepre-shaped, compressed mixture into a granule.
 13. A method of removingcontaminates from an area of contamination comprising: providing aneffective amount of a fibrous organic portion capable of supportingbacterial growth; providing an effective amount of an inorganic portionincluding at least one multivalent metal capable of removing organicchemical contaminants; compounding together the fibrous organic portionand the inorganic portion to form a pre-shaped, compressed mixture; andplacing the pre-shaped, compressed mixture in the area of contaminationto form a permeable reactive barrier for decontamination.
 14. The methodof claim 13, wherein the metal is taken from the group consisting ofzinc, copper, cobalt, nickel, and mixtures thereof.
 15. The method ofclaim 13, wherein the metal is taken from the group consisting of iron,magnesium, and mixtures thereof.
 16. The method of claim 13, wherein thefibrous organic material is plant matter.
 17. The method of claim 13,wherein the plant matter is leguminous plant matter.
 18. The method ofclaim 13 further comprising nitrogenous material.
 19. The method ofclaim 13 further comprising simple carbon sources.
 20. The method ofclaim 13 further comprising complex carbon sources.
 21. The method ofclaim 13 further comprising shaping the pre-shaped, compressed mixtureinto a pellet.
 22. The method of claim 13 further comprising shaping thepre-shaped, compressed mixture into a cube.
 23. The method of claim 13further comprising shaping the pre-shaped, compressed mixture into agranule.
 24. The method of claim 13 further comprising porosityenhancers.
 25. The method of claim 24, wherein the porosity enhancersare take from the group consisting of sand, glass particles, glassfibers, glass filaments, and mixtures thereof.
 26. The method of claim13 further comprising at least one lipid.
 27. The method of claim 13further comprising between about 5% and about 20% weight by weight ofthe multivalent metal; between about 5% and about 80% weight by weightof the fibrous organic portion; up to about 90% weight by weight of aporosity enhancer; and between about 1% and 2% lipid.